What Size Hot Water System Does My Family Need? A Simple Guide
Choosing the right hot water system size can feel like trying to guess how many sausages you'll need for a backyard BBQ - get it wrong and someone's going cold! But don't worry, we've got the simple breakdown to help you pick the perfect size for your family.
Ever had that moment when you're enjoying a lovely hot shower and suddenly it turns icy cold? That's usually a sign your hot water system isn't quite up to the task. Getting the size right isn't just about comfort - it's about efficiency and saving money too.
The Golden Rule: 50 Litres Per Person
As a general rule of thumb, plan for about 50 litres of hot water per person per day. This accounts for showers, washing up, and all those other hot water needs that pop up throughout the day.
- Small households (1-2 people): 50-80L storage tank or compact continuous flow system
- Medium families (3-4 people): 160-250L storage tank or 20-24L/min continuous flow
- Large families (5+ people): 250-400L storage tank or 26L/min continuous flow
Storage Tanks vs Continuous Flow: What's the Difference?
Think of storage tanks like having a big thermos of hot water ready to go - they store heated water for when you need it. Continuous flow systems (also called instantaneous systems) are more like having a personal chef who heats water on demand.
Storage tanks need to be sized based on your family's peak usage - like when everyone's showering before work and school. Continuous flow systems are sized by their flow rate (litres per minute) to handle multiple showers running at once.
Key Factors That Affect Your Choice
- Your family's morning routine - if everyone showers at the same time, you'll need more capacity
- Future plans - expecting more kids? Planning for guests? Think ahead
- Your local climate - colder areas might need slightly larger systems
- Energy source - gas systems typically recover faster than electric
Real-World Examples for Australian Families
For a typical family of four with two adults and two kids, a 160-250L storage tank or a 20-24L/min continuous flow unit usually hits the sweet spot. This gives you enough hot water for morning showers, washing up after dinner, and the occasional extra-long bath.
If you've got teenagers who think showers are their personal spa sessions, or if you often have guests staying, consider going up a size. It's better to have a bit extra than to run out when you need it most.
Final Takeaway: Think Bigger Than You Think
When in doubt, it's usually better to size up rather than down. A slightly larger system might cost a bit more upfront, but it'll save you from cold showers and the frustration of running out of hot water during peak times. Plus, it gives you room to grow without needing to upgrade again in a few years.
Remember, these are general guidelines - your specific needs might vary based on your family's habits and your home's setup. When you're ready to make the switch, chat with a local plumber who can assess your situation and recommend the perfect fit for your family's hot water needs.